Difference between revisions of "Object and Data Structure Basics"

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Line 26: Line 26:
  mydict2['k2'][2]
  mydict2['k2'][2]
  mydict2['k3']['insidekey']
  mydict2['k3']['insidekey']
Add to dictonary
mydict2['k4'] = 300

Revision as of 01:57, 3 January 2019

List

mylist= ['string', 1,2,3]
len(mylist) # get length of list
Result 3

Get part of a list (Slicing)

mylist[1:] gets from index one to the end
result 1,2,3

Concatenate list

another_list = [5,6]
newlist = mylist + anohter_list
result ['string', 1,2,3,5,6]

Add an item to the end of a list

newlist.append('hello')

Remove item from list

newlist.pop() # will pop last item
newlist.pop(0) # will pop index item 0

Sort and Reverse

newlist.sort() # sort list in place, which means you have to call newlist again to get the sorted results. you cannot do x = newlist.sort() becasue it will return nothing
numlist.reverse() # reverse in place

Dictionaries

Has key value pairs

mydict = {'key1':'value1', 'key2':'value2'}
mydict[key1]
out: value1
mydict2 = {'k1':123, 'k2':[0,1,2], 'k3':{'insidekey':100}}
mydict2['k2'][2]
mydict2['k3']['insidekey']

Add to dictonary

mydict2['k4'] = 300